Titanium oxide takes shape

Scientists at the US Department of Energy's

have developed new ways to make or modify nanorods and nanotubes of titanium oxide, a material used in a variety of industrial and medical applications.

The methods and new titanium oxide materials may lead to improved catalysts for hydrogen production, more efficient solar cells, and more protective sunscreens.

In one study, the scientists enhanced the ability of titanium oxide to absorb light.

‘Titanium dioxide's ability to absorb light is one the main reasons it is so useful in industrial and medical applications,’ said Wei-Qiang Han, a scientist at Brookhaven's Center for Functional Nanomaterials (CFN). It is used as a photocatalyst for converting sunlight to electricity in solar cells and also has applications in the production of hydrogen, in gas sensors, in batteries, and in using sunlight to degrade some environmental contaminants. It is also an ingredient in sunscreen.

Scientists have explored ways to improve the light-absorbing capability of titanium oxide by ‘doping’ the material with added metals. Han and his colleagues took a new approach. They enhanced the material's light-absorption capability by introducing nanocavities, which are enclosed pockets within the 100nm diameter solid titanium oxide rods.